Extensible rule



June 23, 1953 L, E. SMILEY 25642567 y EXTENSIBLE RULE Filed April 25,195o v 2 sheets-shew 1 INVENTOR.

' Lon/:LL 5M/4:7

BY v om .Mb

ATTORNEYS.

June 23, 1953 l.. E. SMILEY 2,642,667

' EXTENSIBLE RULE Filed April 25, `1950 2 Sheets-Sheet 2 INVENTOR.Lowfl. L-LH/AAY Patented June 23, 1953 UNITED .STATES PATENT OFFICEEXTENSIBLE 'RULE Lowell E. Smiley, Lorain, `Ohio Application April 25,1950, Serial No. 157,923

-141 Claims. (Cl. 33'-f1671) This Ainvention relates to measuringydevices and, more particularlyto a folding rule comprising a pluralityof sections pivotally connected end to Iend and havingfanextensionslidein vone Vvofl the end sections thereof.

It has been Inot uncommonl to fprovide Afolding "rules vwith aslidable'member 'mounted in an -end section thereof; making suchv rulesespecially convenient for taking .inside measurements. The usermerelyunfolds the rule (starting with thatend which carries .the extensionslide) -to `approximately the distance to bemeasured and lthen slidesthe extensionmember outwardly until the distance between the two pointsbeing measured .is Vaccurately' recorded` on. the rule. v'How-1everpwherea measurement is to be taken between-two points difficultA ofdirect access, it-is frequentlyiirnpossiblev to remove the rule -forreading ywithout -flrstl somewhat retracting the extended slide.Accurate measurementsin such situations have consequently` been mostdiiieult .Ito-.obtain fAprima-ry object of my inventionA is,vaccordingly, to provide an .extensibley rule particularly V.adapted tothe .taking` ofvprecisemeasurements '.in'awkward` situations,..as fwhereboth ends of the rule must be insertedthrough constricted vopenings.

Another/object lis to provide: an extensible; rule --With--a slidingmember; mountedinan endsecvtionthereof which. maybe retractedin ordertoremove the rule, but which Will .then .snap

v .back and return to its original extended position,

smi another object is improvise@ resiuentv sliding member .for the. endsection. ora folding rulel which may be .heldrgid and fully extended--while the measurementfis being taken.

,Other objects of my vinventionwill appear. as the description proceeds.

;Tostheaccomplishment of the foregoing and lrelated endssaid Ainventionthen .comprises-.the features hereinafter fully. described and Vpar-.ticularly pointedout .in Ythe claims, the following description-and,the annexed drawing setting forthV in detailcertain illustrative.embodiments ofthe invention, these'being. indicative, howeveiyof buti-afew of the. various ways in VV.which theY principle `of `the' inventionmay` be employed 'In said annexeddrawing:

'-Fig. l1 is `a view of one embodimentof myinlvention. in Ithe form y ofa folding extensible. rule shown-as t-would lbe .used to..-ascertain.the :dis-

. 2 l tance between two inside points,.one of which has a` constrictedentrance;

Fig. 2 is a top plan view of -an end section carrying an extensionslide, and lshowing also` a Y portion of the next adjacent section ofthe rule;

Fig. 3-is a side elevation of such end `section with the extensionslidepartially extended;

-Fig. 4 -is a viewtaken alongwthe line 4-4 on Fig. 3;

Fig. 5 is: similar to Fig. 4 but shows the clamping device -in analternate position; y

Fig.-6. is aside elevation of a portionv of the extension slide, partlyin section, Aand'with the clamping device in the Fig. 4 position;

Fig. 7 is similar to Fig. 6, but shows the clamping device in the Fig. 5position;

Fig. 8 is a transverse sectional view of a folding rule having amodified formv ,of extension slide, and showing also the. clampingdevicefor in the Fig. 8 position; and

Fig. 11 is an enlarged sectional view taken valong 'the line I I-I I onFig. y8.

vReferring now to Figs. 1-7 of. the drawing .and more particularly toFig. 1, the preferred embodiment of myinvention there shown comprises afolding rule. composed of V.aplurality .of sections, identiedbynumeralsI to I2, which are pivotally connectedend toend in such man- .nerfas tosnap into longitudinally aligned` series r when opened. The rule may,ofcourse, be of any suitable length, .the standard folding rule oftwelve sections vwith eight inches to` each vsection `having beenchosenfor purposes of illustration only.

End section I is provided with a longitudinally extending groove I3 ofinverted T-shaped crosssection in which is slidably mounted an.extension slide of similar cross-section. The Yexten-- sion. slidecomprises two longitudinally spaced members I4 Vand I5, the-formerhaving a groove I6 extending longitudinally of the underside thereof,with a shoulder I1 secured thereto and providing a oonstricted entranceto such groove .at the right-hand end of such member as viewed inFigs.-6 and '7. A rod I8 connects such members I4 and I5, being mountedfor sliding move- 4ment in the groove I6 of member I4 and, of

course, passing through a hole inshoulder l1, and rigidly secured. tomember I5. A compres- ,sion spring I9, carried' by rod I8 and interposedbetween such members, is eiiective resiliently to space them apart.Secured to such rod IS to the side of shoulder i7 opposite spring I9 isa collar 2B which is adapted to engage such shoulder and thereby providea maximum limit to the longitudinal spacing of members I and I5.

A laterally projecting stud 2l -is secured to one side of member I4(Figs. 4 and 5) which isadapted to slide in .longitudinally extendinggroove or slideway 23 formed in the side of groove I3. Such slideway isopen at the lefthand end of section I to permit of assembly (Fig. 2) andterminates short of the right-hand end thereof forming a. shoulder 24appropriately lo- K cated so as to engage such stud to prevent slidemember I5 from being pushed to the right all the: Although member I5.1

way out of end section I. is only slightly more than 61/2 inches long(see -wings which o-verlie the upper surface of end sec- .tion I beneaththe lower extremities of hinge Fig. 2), still the extension slide needproject no more than 6 inches to record any and all interf mediatedistances within the total length of the instrument. This means thatthegap in the slide assembly never reaches the end of section I andslide member I5 is always properly seated in such section.

A clamp 25 is hinged to member I4 by means of depending e-ars or hingemembers 29 and 2 which -may be formed integrally with clamp 25, suchhinge minating above the bottom surface of groove I3, being formed toreceive a transverse hinge pin 29 mounted in member I4.

The lower extremities of suchV hinge members are eccentric to hinge pin29 and therefore serve as cams when clamp 25 is rocked. Anexible metalplate 30, secured at its righthand end (Figlr) to the bottom face ofmember Ill, is interposed between the surface of groove I3 and suchlower cam extremities of hinge members 26 and 2l. Clamp 25 is alsoprovided with a depending projection or tongue 3I which likewiseextendsthrough slot'28 and abuts the 'end of l'od I8 (in one rotativeposition of clamp 25), thereby locking rod I8 to retain members It 'andI5 in fully spaced relationship.

Referring next to Figs. 8-11, a folding rule having an end section witha modied form of construction is there illustrated. Y The longitudinallyextending groove 32 of end section I differs fro-m the groove I3 of theembodiment first described in that the lower portion thereof is hollowedout in order to accommodate the connecting rod IB which is locatedbeneath the extension slide, being xe'dly secured at one end to the post33 of member I5 and slidably secured to member I4' by collars 34depending therefrom. Spring I9 is carried by such rod fand interposedbetween xed collars 35 and 3S depending respectively from. members Illand I5 and slidably embracing the rod. Secured to the rod to theopposite side of collar 35 from spring I9 is a collar 20 which isadapted to engage the collar 35 and thereby serve as a stopto provide amaximum limit to the longitudinal spacing of members I4 and l5. Clamp 25is hinged to the upper face of member I3', having depending ears orhinge members 31 and 38 rwhich may be formed integrally with the clamp,such hinge members extending laterally outwardly and downwardly andterminating above the surface of section I to receive hinge pin 39carried by upstanding hinge members 49 and 4I secured to the upper faceof member I4'.

The lower extremities of such hinge members members extending downwardlythrough a vertical slot 28 in member I4 and terslipping, is therebyassured.

' members 31 and 33.

Having thus described certain preferred embodimentscf my invention, theoperation thereofi vbecomes readily apparent. For example,

b shouldthe userdesire to measure the distance betweenltwo points asillustrated in Fig. 1 of th-e drawing, he will merely unfold the rule,starting with end section I,`vto approximately the dis-- Ytance betweenthe twopoints-"to be measured.V vThe remainingga'p `may then be coveredby,` means of the vextension slide which is moved out- Y wardly untilthe forward end of member I5 engages such measuring po`i-nt.'f0f course,asl the extension slide is `moved` outwardly, it willr be understoodthat clamp 25 w'illbe-in theposition shownin Figs. 5 and 'l with theVdepending tongue labutting the end of rod I8,l thusrho-lding memvbersIll `'and I5 rigidly infully spaced relationship. The innercurveoftonguel comprises' an arc having hinge'pivot`29`fasf`its centerand the end of rod I8 is similarly curved. Consequently,

when the operator rocks clamp 25 forwardly with his thumb, tongue 3|will maintain engagement with rod I8 to holdmemb'e'rs' Ill and I5'rigidly apart until the cams 26 and 2 have turned sufficiently to lockslide member Ill-in sectionI. An accurate measurement, without anyaccidental When the rule and "extensie slide havebeen openedsufficiently to record thedistance between rthe two points ofmeasure-frientjthe user will press forwardly upon clamp-25 (inaclockwise direction as viewed in Fig. 7) causing the lower extremitiesof hinge members 26 and 2li/o. cam downwardly upon flexible plate 39pressing the latter tightly between s uch hinge members and the surfaceoaf groove I3. InY the embodiment illustrated in Figs. 8-11, flexibleplate M- will, of course, be held tightly between hinge members and 3 8andthe upper face of end section I. With clamp 25 Vthus Yrotated as faras possible in a clockwise direction,

,thel cam's'urfaces'of the hinge members of such clamp are eiective tourge the -hinge pin upwardly, thus causing member I2 to be pressedagainst the slideways ofthe groove of section I, locking such membertightly relative thereto. Depending tongue 3|V (and corresponding tongued2) is shaped and dimensioned rto maintain YContact with the end of rodor plunger I3 until slide member I4 has been nrmly'clampedfin positionbyrocking of','cla;np 25. Consequently, there is no possibilityfofVvmember j Iii being inadvertently shifted after lonce having beenproperly posi'- tioned. Inthecase of the Fig. 11v` form this g would"mean that clamping cams 37 and -38 extension slide against theaction ofcompression spring 'I 9. The rule is thus veasily removed withf-ullyspaced, A flexible` out losing lthe' record of measurement since member.Ifwill; snap back fully spaced from member I4 against the stop or collar20 by action of compression springr I9.

It might be emphasized 4that the folding rule of .my inventionisparticularly useful Where a high degree of accuracy is desired,`requiring that the rule vbe opened until it so tightly engages bothmeasuring points that it cannot be removedby merely folding an opensection. Instead, the resilient. extension slide is merely collapsed afraction of an inch (it has been foundv that 1/8"1/2" vis, ordinarilysufficient) whereupon the rule may be veasily and quickly removed whileretaining an accurate record of measurement. It will also .be

appreciated that the sections of my folding rule .may be of any desiredlength, and the principle of the invention may, of course, be utilizedwith other than folding rules. The gap between members I 4, and I5 mayalso be covered and concealed, if desired, by provision of an upperflange on one such member adapted to overlie the other member when thespring is further compressed.

Other modes of applying the principle of the 'invention may be employed,change beingv made as regards the details described, provided the fea-'tures stated in any of the following claims, or the equivalent of such,be employed. s v Itherefore particularly point out and distinctly 'claimas my invention: 1. In an extensible folding rule comprising apluralityof sections pivotally connected en-d to end, a longitudinal'slideway in one of the end sections,l an extension slide mounted forsliding movement therein comprising two longitudinally Vspacedinterconnected members resiliently'spaced apart; a'stop limiting suchmaximum longitudinal spacing of said members, clamping'means for`relea'sably locking the inner one of said members tosuch-end section,and lock means selectively operative to. llock said members in fullyspa-ced relation. 2.'In an extensible folding rule comprisinga pluralityof sectionspivotally connectedend to end,v a longitudinal slideway inone of the end having a shoulderv atY the end,` adjacentthe'iirst one ofsaid members, resilient lmeans .carriedrby Hsaid rod and interposedbetween said two members adaptedresiliently .to space said members lapart, a collar secured to said rod to the sideof j said-'shoulderopposite said resilient means and adapted to engage said shoulder,thereby limiting such maximum longitudinal spacing of said two members,clamping means for releasably locking `the inner one of said membersl tosuch end section, and lock means vselectively operative to lock saidmembers in fully spaced relation.

` 3.' In an extensible folding rule comprising a Aplurality of sectionspivotally connected end to end, a longitudinal slideway `in one of theend sections, an extension slide mounted for sliding 4movement thereincomprising two longitudinally spacedl interconnected members resilientlyspaced apart, clamping means for releasably locking the inner one ofsaid members to suchend section, `said' clamping means being hingedlysecured to said inner member and having, a depending ear terminatingabovethe surface of said slideway,

and a flexible plate secured to the undersurface of said.` inner memberHinterposed .between said depending ear and the 'surface of saidslideway, ysaid depending ear being adapted, in one rotative position ofsaid ,clamping means, to engage said plate and hold the latterk tightlyagainst the .surface of said slideway. f

-4. In an extensible folding, rule comprisingl a vplurality of sectionspivotally connected end ,to en-d, a longitudinal slideway in one of theend sections, an extension Yslide mounted for sliding movement thereincomprising two longitudinally .spaced interconnected members resilientlyspaced apart, a stop limiting such maximum longitudinal .spacing of saidmembers, clamping means for releasably locking the inner one of` saidmembers ,to suchend section, said. clamping means being hingedly securedto said inner member and havinga pair of depending ears laterally spacedand Aterminating above the surface of said slideway, a

vflexible plate secured to the under surface of .said

inner member. interposedbetween said depending ears and the surface ofsaid slideway, said depending ears being adapted, in one rotativeposition of said clamping means, to engage said plate and hold thelatter tightly against the surface of `said slideway, and manuallyoperable lock means selectively operative to lock said members in fullyspaced relation.

5. In an extensible folding rule comprising Ya plurality of sectionspivotally connected end. to end, a longitudinal slideway in one of theend sections, an extension slide mountedV for sliding movement thereincomprising two longitudinally spaced interconnected members, a slidewayin the inner one of said members having a shoulder at the end adjacentthe outer one of said members, a rod mounted for sliding movement insaid second slideway and secured to said outer member, spring meanscarried by said rod and interposed between said two members adaptedresiliently to space said members apart, a collar securedto said rod toythe side of. said shoulder opposite said spring means and adapted toengage said shoulder, therebylimiting such Vmaximum longitudinal spacingof said two members, clamp-ing means for releasably locking said innermember tosuch end section, said clamping means being hingedly secured tosaid inner member and having a tongue depending therefrom adapted, inonek rotative positionV of said clamping means, to `engage an vend ofsaid rod, therebylocking said two membersin fully spaced relation, saidclamping means also Y.having a pair of depending ears laterally spacedand terminating above the surface of the jrst said slideway, `and aflexible plate secured to the under-surface of said inner member interpposed between said depending ears and the ,sur-

. face lof the first` saidv slideway, said depending ears being adapted,in an alternate rotative position of said clamping means, to engage saidplate to one of said members for slidably connecting` `said memberstogether, a collar on the other ofsaid members slidably embracing saidrod,

.acollar` secured to said rodadapted to engage i said first collar andlimit such maximum longitudinal spacing of said two members, resilientmeans carried by said rod adapted resiliently to space said two membersapart,v clamping 'means for releasablyV locking the inner one of saidYmembers to suchend section, and lock means selectively operative tolock said two vmembers in fully spaced relation.

'7, In an extensible folding rule comprisinga V'pluralityof sectionspivotally connected end to the inner one of said members to such endsection, said clamping means vbeing, hingedly secured to the outer faceof said inner member and having a depending ear terminating above theouter face of such end section, and a flexible 'plate vsecured to saidinner member 'lying interposed between said depending ear and the outerface of such end section, said depending ear being adapted, in one.rotative position lof said clamping means, to engage said plate and holdV*the latter tightly against the outer face of such .end section.

8. In an extensible folding rule comprising a plurality of sectionspivotally connected end to end, a longitudinal slideway in one of theend sections, an extension slide mounted for sliding movement thereincomprising two lone gitudinally spaced interconnected membersresiliently spaced apart, a stop limiting such maximum longitudinalspacing of said members, clamping means for releasably looking the inneroneof said members to such end section, said clamping meansbeinghingedly secured to the outer face of said inner member and havinga pair of depending ears laterally spaced and terminating above theouter face of such end section; a ilexiblel plate secured to said innermember having side portions which lie interposed between said dependingears andthe outer vface of said end sections'aid depending ears beingadapted, in one rotative position of said clamping means to engage saidplate and hold the latter tightly against the outer face of such endsection, `and manually operable lock means operative to llook said twomembers in fully spacedrelation.

9.A In an extensible folding rule comprising a pluralityoi sectionspivotally connected end to Y.

end, a longitudinal slideway in one of the end sections, an extensionslide mounted for sliding movement therein comprising two longitudinallyspaced interconnected members, a rod secured tothe outer one of saidmembers for slidably connecting said members, a collar on the inner oneof said membersv slidably embracing said rod, a collar secured to saidrod adapted to engage said iirst collar and limit such maximumvlongitudinal spacing of said two members,

spring means carried by said rod adapted resiliently to space said twomembers apart, clamping means for releasably locking said inner memberto such end section, said clamping means being hingedly secured to theouter face 0f said inner member and having a tongue depending therefromadapted, in one rotative position of said clamping means, to engage anend of said rod, thereby locking said two members in fully spacedrelation, said clamping means also having a pair of depending earslaterally spaced and terminating above the outer face of such endsection, `and a flexible plate secured to said inner member having sideportions which lie interposed between said depend- Ving ears and theouter faceofsuch endv section, said depending earsbeing adapted, inlranalteinate rotative position of said clamping means,

to engagesaid plate and hold the lattertightly Y against the outerfaceof suchend section.

10. A linear measuring instrument'including a'slide adapted to beextended therefrom, said slide comprising two axially space dmembers, lresilient means urgingsaid members apart, stopV means limiting themaximum extent of such axialspacing, means releasably rigidly securingwhen said means rigidly securing said membersin spaced relationship isreleased. Y

11. A linearmeasuring instrument including a slide adapted to beextended therefroms`aid slide comprising two' axially spaced members,resilient Vmeans adapted to urge said members apart, means adapted tolimit the extent of such axial spacing, a Yrod secured' to one of saidmembers and extending 'parallel to the other said member, and rockableclamping means" on said latter member adapted to clamp said memberagainst movement and adapted in unclamped position to engage said rod tohold the other said member in rigidly spaced relationship thereto andonly in clamped position to release said rod to permit movement of. saidothermember yagainst the action of said resilient means.

l2. A linear measuring instrument comprisingabodyportion and a slideadapted to be extended therefrom, said slide comprising two axiallyAspaced members, resilient means adapted to urge said members apart,means adapted to limit the extent of such axial spacing,.one of saidmembers bearing measuring indicia andadapted to be extended from saidbody portion Yand the lother said member being provided with clampingAmeans and adapted to remain seated in said body Y portion, a rodsecured to'said extensible'member and. extending parallel to the othersaid member, and a clamp pivotally mounted on said, latter memberincluding a catch adapted to engage the end of said rod tov hold theVsaid extensible member in rigidly spaced relationship andY in` .cludingclamping means operative when rocked lto clamp said slide member onwhichitis thus mounted to said body portion, said catch and Arod end beingcurved in their engaging portions on an arc centered on such pivot anddimensioned to maintain partial engagement until said clamp hasbeenrocked suii'icientlypto secure said slide member on which it ismounted to said body portion. y Y

13. A linear measuring instrument having a longitudinal slidewaycommunicating with an end thereof, an extensionrslide mounted forsliding movement therein comprising two lonlongitudinal slidewaycommunicating, with an end thereof, an extension slide mounted forsliding movement therein comprising ytwo longitudmally spacedinterconnected members, Aresil- References Cited in the le of thispatent UNITED STATES PATENTS Number Name Date' Voggenreiter Dec. 23,'1913 Buck oct. 24, 1922 Emery May 4, 1926 ISwanson Jan. 20, 1942

